송대(宋代) 각국(各國) 해상(海商)의 왕래(往來)와 국적(國籍) 판별(判別)의 근거(根據) -특히 고려해상(高麗海商)의 활동(活動)과 관련(關聯)하여-

In Song Dynasty, there were so many ships and merchants flocking to the coastal port using a seasonal wind. Official of Song customs issued to its own marine traders ``Gongbing`` guaranteeing identity. Likewise other countries issued ``Gongbing`` to their marine traders. Through these ``Gongbing``, China had a good grasp of nationality of ships and merchants. Koryo also judged nationality of ships and merchants through Gongbing. Consequently, Gongbing functioned as today`s passport. There are records on Korea ships and merchant in the historical material of the Song Dynasty. It was judged by Customs offices(市舶司) of Song Dynasty based on the Gongbing issued by Koryo. In the meantime there were two types of Korea`s marine merchant. One type was Korean and the other was naturalized Korean from China. That is both types of Korean marine traders took part in trade with Song China. Therefore at that time both Song`s merchant in nationality and Korean merchant in nationality participated in marine trade of East Asia.